From e93d4166b40a84df83c4d5cb4c709d022808ef9b Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Mon, 24 Jun 2024 17:59:05 -0700 Subject: mm: memcg: put cgroup v1-specific code under a config option Put legacy cgroup v1 memory controller code under a new CONFIG_MEMCG_V1 config option. The option is turned off by default. Nobody except those who are still using cgroup v1 should turn it on. If the option is not set, memory controller can still be mounted under cgroup v1, but none of memcg-specific control files are present. Please note, that not all cgroup v1's memory controller code is guarded yet (but most of it), it's a subject for some follow-up work. Thanks to Michal Hocko for providing a better Kconfig option description. [roman.gushchin@linux.dev: better config option description provided by Michal] Link: https://lkml.kernel.org/r/ZnxXNtvqllc9CDoo@google.com Link: https://lkml.kernel.org/r/20240625005906.106920-14-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin Acked-by: Michal Hocko Acked-by: Shakeel Butt Cc: Johannes Weiner Cc: Matthew Wilcox (Oracle) Cc: Muchun Song Signed-off-by: Andrew Morton --- mm/memcontrol.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'mm/memcontrol.c') diff --git a/mm/memcontrol.c b/mm/memcontrol.c index b47c00f60332..53a8491634b9 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4398,18 +4398,20 @@ struct cgroup_subsys memory_cgrp_subsys = { .css_free = mem_cgroup_css_free, .css_reset = mem_cgroup_css_reset, .css_rstat_flush = mem_cgroup_css_rstat_flush, - .can_attach = memcg1_can_attach, #if defined(CONFIG_LRU_GEN) || defined(CONFIG_MEMCG_KMEM) .attach = mem_cgroup_attach, #endif - .cancel_attach = memcg1_cancel_attach, - .post_attach = memcg1_move_task, #ifdef CONFIG_MEMCG_KMEM .fork = mem_cgroup_fork, .exit = mem_cgroup_exit, #endif .dfl_cftypes = memory_files, +#ifdef CONFIG_MEMCG_V1 + .can_attach = memcg1_can_attach, + .cancel_attach = memcg1_cancel_attach, + .post_attach = memcg1_move_task, .legacy_cftypes = mem_cgroup_legacy_files, +#endif .early_init = 0, }; @@ -5581,7 +5583,9 @@ static int __init mem_cgroup_swap_init(void) return 0; WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, swap_files)); +#ifdef CONFIG_MEMCG_V1 WARN_ON(cgroup_add_legacy_cftypes(&memory_cgrp_subsys, memsw_files)); +#endif #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP) WARN_ON(cgroup_add_dfl_cftypes(&memory_cgrp_subsys, zswap_files)); #endif -- cgit v1.2.3